A comparable method and a comparable device for cleaning crankcase ventilation gases are known from MTZ Motortechnische Zeitschrift 60 (1999) 7/8. In this case, there is a central wire electrode that is operated with a voltage below the breakdown voltage and which is encircled at a distance by a coaxial counter-electrode as the anode, so that the gas stream to be cleaned can flow through this tubular counter-electrode.
In view of the flow rate of the gas to be cleaned, this device is not suitable for effective cleaning because of its limited length. In addition, there is a considerable risk of fouling the wire electrode, which may result in the device operating in a non-homogeneous way and thus ineffectively.
In addition, particle separators, which precipitate charged particles from a gas stream at a flat electrode by means of electrical field forces, exist in a variety of embodiments, for example, as an electrostatic dust filter or as a so-called oil separator for cleaning crankcase ventilation gases. These embodiments all share a common feature that the electrical field is generated with as high an electrical field strength as possible, although the electrical voltages have to be significantly below the breakdown voltage for the electrode gap of such electronically operated separators. Usually, the operating voltage is less than half the breakdown voltage, in order to avoid uncontrolled local discharges (electrical voltage breakdown).
The result is low efficiency and a long path is required for the actual separation, especially if the flow rate of the gas conveying the particles is high.
In addition, large scale treatments of exhaust gas for clean air can be carried out with plasma technology. In this case, a plasma technology with pulsed electric filters is used, where the pulse exhibits peak power of 50 megawatts at pulse rates of 200 hertz. The plasmas in these particle filters are superposed with high voltage pulses. Such a device is expedient only in connection with large scale industrial plants.